In Alberta today about 650,000 barrels per day of mined bitumen is upgraded to synthetic crude oil (SCO). The mining is carried out in a vast area in northern Alberta (Athabasca region), where tar sands/oil sands are abundant. The SCO has several advantages as it has no residue. It is also low in sulphur and nitrogen. However, this SCO or even bitumen from that region in Alberta is rich in aromatics. To date, effort has been focused in trying to use this SCO or bitumen to produce distillates for the automobile industry—mainly diesel and gasoline. This invention arises from a focused study on how best to use the highly aromatic feedstock and transform it into a petrochemical feed (i.e. to paraffins for the production of olefins in steam crackers).
Planned expansions in the Alberta oil sands industry show that there will be large quantities of bitumen and tar sands derived oils in the market with the potential of having reasonable prices, making them attractive to use as feed to petrochemical plants.
U.S. Pat. No. 4,202,758 issued May 13, 1980 in the name of O'Hara et al., assigned to UOP Inc. teaches a process for hydroprocessing hydrocarbons and in particular the ring opening of aromatic ring compounds in a feed stream to produce saturated hydrocarbons and in particular jet fuel. The patent teaches the use of group VIB or group VIII catalyst on a zeolite support for such hydroprocessing. The feedstock appears to be any feedstock which will take up hydrogen. The process is not an integrated process for the treatment of pyrolysis fuel oil and/or gas oil preferably heavy gas oil derived from oil sands or bitumen.
U.S. Pat. No. 5,152,885 issued Oct. 26, 1992 to Singhal et al., assigned to Exxon Research and Engineering Company teaches a process for removing heteroatoms from heavy feedstocks such as heavy coker gas oil or coal derived gas oils, or shale oils. The feedstock is treated with a catalyst comprising one or more noble metals such as platinum, palladium, rhodium and iridium at least one group 6, 8, 9, 10 or 11 metals such as nickel, iron or copper, supported on alumina. The process is not an integrated process for the treatment of pyrolysis fuel oil and/or gas oil preferably heavy oils from an upgrader which processes oils derived from tar sands or bitumen.
U.S. Pat. No. 5,520,799 issued May 28, 1996 to Brown et al., assigned to Mobil Oil Corporation, teaches a process for hydroprocessing a light cycle oil having high and low heteroatom contents to produce, jet fuel and the like. The light cycle oil is typically the co-product from a fluidized bed catalytic cracking unit and typically contains bicyclic aromatic compounds. The process is not an integrated process for the treatment of pyrolysis fuel oil and/or gas oils, preferably from a tar sands upgrader, and transforming them into petrochemicals feedstock.
The present invention seeks to provide an integrated process for the treatment of an aromatic rich heavy stream which is either an aromatic rich stream obtained by the distillation of a pyrolysis fuel oil, and/or from the catalytic cracking of gas oils derived from bitumen or oil sands processing, or both in a weight ratio of 10:1 to 1:10 in the presence of a catalyst to produce a stream of saturated hydrocarbons such as paraffins and a co-product stream. Preferably the saturated hydrocarbon stream may be used in further petrochemicals processes such as steam cracking to produce olefins.